Hi cadenemory,
I'm nonbinary AFAB and currently on a low dose of T for PMDD (premenstrual dysphoric disorder--basically terrible mood symptoms) and some gender dysphoria. It's working for me.
With PCOS, you want to talk to a good doctor who understands all that. I'm not in any way a doctor and only know a little about PCOS, but it could mean you already have a higher than "average female" level of T in your system -- so I don't know how that would interact with additional low dose T. To my knowledge PCOS has to do with insulin levels more than T levels.
I've been on T for almost 4 months, starting at a lower dose and now 50mg/day. I feel a lot calmer. I'm still getting a period but the symptoms around it are about 1/5 of what they were. I'm appreciating having more energy and it seems like my hips are getting less wide, which I'm very happy about.
I hope that helps!